Render Twig component from Twig extension

[michalschroeder]

Hi and happy new year :)

I'm trying to use an anonymous Twig component in my Twig extension, something like this:

templates/components/Test.html.twig

<div {{ attributes }}>
    Test
</div>

My Twig extension class

final class TestExtension extends AbstractExtension
{
    /**
     * @return list<TwigFilter>
     */
    #[\Override]
    public function getFilters(): array
    {
        return [
            new TwigFilter(
                'test',
                $this->test(...),
                [
                    'is_safe' => ['html'],
                ],
            ),
        ];
    }

    public function test(): string
    {
        return <<<'HTML'
                <twig:Test>TEST</twig:Test>
            HTML;
    }
}

The effect is that it renders this as a simple string <twig:Test>TEST</twig:Test> in the HTML output, so it's not detecting that it should be rendered as a Twig component. Is that expected behavior? Or I'm using it wrongly?

I came up with two different solutions to make it work.

1. Use Twig Environment like this:

final class TestExtension extends AbstractExtension
{
    ...

    public function test(Environment $twig): string
    {
        $template = <<<'HTML'
               <twig:Test>TEST</twig:Test>
            HTML;

        return $twig->createTemplate($template)->render();
    }
}

2. Use ComponentRendererInterface like this

final class TestExtension extends AbstractExtension
{
    ...

    public function test(): string
    {
        return $this->componentRenderer->createAndRender('Test');
    }
}

But TBH I'm not convinced if that's the correct solution. From my perspective both have downsides and I'm curious what's the recommended way to make it work?

[GromNaN]

The first solution will require a runtime compilation of the template, which should be avoided if possible. Also, streaming would be preferred.

    public function test(\Twig\Environment $env): iterable
    {
        yield from $env->createTemplate($html)->stream();
    }
}

But the 2nd option is better, as you avoid a layer of Twig template.

However, the best solution may be to use a macro or an include to keep everything in Twig.